In the development of control systems for digital devices, it has long been a problem as to how to sufficiently implement logic circuitry in order to provide control signals to regulate and control a target digital device. In earlier periods of technology, analog signals and analog circuitry was used to generate analog signals which would be transmitted to analog target devices in order to control their operation. With the advent of digital logic circuitry and with the great flexibility of use with Field Programmable Gate Arrays (FPGAs) and also with the use of Application Specific Integrated Circuits (ASICs), there can be great efficiencies provided in using digital busses carrying multiple-bit digital signals which can be digitally processed in order to provide the desired or required control signals for target digital devices.
Many of the Input/Output and control signals in digital circuitry are seen to have mathematical relationships to each other. Thus, with the use of functional relationship generators which can be implemented in digital circuitry, it can be found to be quite efficient to use various signals and parameters in order to develop a desired output control signal.
The presently described system and method illustrates how the mathematical and functional relationships of digital signals in electronic circuitry can be represented by the use of simple, standardized logic design elements. These systems and methods can be built into simple, industry-standard programmable logic elements, for example, such as PALs (Programmable Logic Arrays) or Field Programmable Gate Arrays (FPGA's).
Digital computers and related logic require "digital" binary values (not an analog voltage or current). If analog circuitry was used, then some form of analog-to-digital conversion was necessary to allow other digital logic to utilize the linear values.
If a linear relationship is created "digitally," then this extra analog-digital conversion circuitry is no longer required.
Also by using single standard FPGA (Field Programmable Gate Array) devices, the cost is reduced and the functions required can be modified and made flexible by the act of simple re-programming.